The present disclosure relates to a harvesting attachment for a harvesting machine, wherein the harvesting attachment comprises a frame which is suitable for holding various harvesting tools, in particular cutting units. During the harvesting operation, the harvesting attachment is moved in a forward direction over a field by means of an agricultural harvesting machine and serves to take up certain crops. For example, the harvesting attachment comprises a cutting unit, a reel and further components required and can be mounted on the front side of a combine-harvester. The harvesting attachment likewise can comprise a corn adapter as it is used in a known corn chopper.
In principle, it is currently largely desired in the agricultural machine industry to offer increasingly broad harvesting attachments for self-propelled harvesting machines, which allow the farmer to harvest a field in a shorter time and with less cross-over. However, the maximum width of the harvesting attachment is limited as regards the stability of the construction due to increasing material stress in dependence on the amount of material used. For example, axial area moments of inertia play an important role here, which represent a measure for the bending resistance of the cross-section of the harvesting attachment. Furthermore, acting torsional forces must also be considered when dimensioning the harvesting attachment. Since broadening the harvesting attachment involves a constant increase in dead weight, the forces acting on the harvesting attachment, in particular the bending moment, thus are further increased.
From DE 10 2004 008 342 A1 a harvesting attachment for a combine-harvester is known, which comprises a frame on which a cross-beam extends horizontally and transverse to the forward direction.
DE 10 2005 016 334 A1 discloses a discharge chute for a field chopper, which comprises a frame-shaped or lattice-shaped supporting assembly.
From DE 956 815 B a frame construction for binding mowers is known, which can be manufactured in a lightweight construction.
AT 180 915 B discloses a self-propelled motor mower, whose cutter bar is configured in a lightweight construction in the form of a profile bar.
From DE 10 2004 059 064 A1 an attachment for agricultural harvesting machines for cutting off, taking up and passing on corn plants is known, in which drum-shaped rotary bodies are used, which are made of lightweight materials, in particular of plastic materials or metallic alloys.
It is the object of the present disclosure to provide an improved construction for a harvesting attachment, which allows a reduction of the dead weight and/or an increase in strength of the harvesting attachment. In particular, the construction in accordance with the present disclosure can enable a broader or larger-dimensioned harvesting attachment.
In accordance with the present disclosure, this object is solved by a harvesting attachment for a harvesting machine comprising a frame which includes an outer wall which defines a cavity, wherein at least one strut is arranged in the cavity. The frame serves to hold further harvesting tools and components, in particular a cutting unit. The cavity can, but need not be completely enclosed by the outer wall. The outer wall in particular includes a front wall and a rear wall. The cavity defined by the front and rear walls of the outer wall possibly can be closed completely by one or two side walls. In accordance with the present disclosure, at least one strut is arranged inside the cavity. The strut is connected with the outer wall. The strut is connected with at least one inner surface of the outer wall defining the cavity. It is desirable that the strut is arranged such that a stabilization of the frame is achieved. As compared to harvesting attachments known from the prior art, a considerable saving of weight is achieved by forming a cavity and at the same time the system of struts inside the cavity, without a loss of stability of the entire construction. Due to the saving of raw materials in the manufacture of the harvesting attachment of the present disclosure, a less expensive production method hence is obtained.
Advantageously, the frame has an L-shaped angular shape. In this embodiment, the outer wall can be divided into a horizontally extending area and an area extending vertical thereto. In an operating position, the longer leg of the L-shaped frame extends in vertical direction and the shorter leg lies in a horizontal plane. In the following paragraphs of the description, the surfaces of the outer wall forming the longer leg of the L-shaped frame are designated as front and rear walls, wherein the vertically extending wall lying on the inner surface of the L-shaped frame is referred to as front wall.
A further advantageous development is characterized in that in its cavity the frame includes at least one cross strut which connects the front and rear walls of the outer wall and extends substantially horizontal, possibly vertical to the side wall. The front and rear walls of the frame are connected with each other by a plurality of cross struts. With the L-shaped angular shape of the frame, exactly two cross struts may be arranged one after the other along an axis parallel to the side wall, which connect the front and rear walls of the leg with each other. The cross struts can include recesses. It is conceivable that the width of at least one cross strut is identical to the distance of the two side walls of the frame, so that the two opposed side walls of the frame likewise are connected with each other by the at least one cross strut.
In accordance with a further advantageous development the frame includes at least one longitudinal strut in its cavity, which connects the front and rear walls of the outer wall and extends substantially vertical, possibly parallel to the side wall. The at least one longitudinal strut extends in vertical direction of the frame, wherein the longitudinal strut is configured so broad that it connects the front and rear walls of the outer wall of the frame with each other. Particularly, a plurality of longitudinal struts are arranged inside the cavity of the frame. With an L-shaped angular shape of the frame, the longitudinal struts thus extend in vertical direction along the longitudinal axis of the longer leg of the L-shaped frame, wherein a longitudinal strut may extend from the apex of the L-shape along the longitudinal axis of the longer leg to the upper end thereof.
It can be provided that at least one strut of the entire strut system includes at least one recess. The recesses are arranged in the strut such that on the one hand a reduction of the total weight of the frame is accomplished and on the other hand the stability of the frame is not impaired.
The frame includes at least one tubular through opening, which extends parallel to the front and rear walls of the outer wall. Particularly advantageously, with an L-shaped configuration of the frame a tubular through opening is arranged at the upper end of the longer leg and a second tubular through opening is arranged in the shorter leg of the L-shaped frame. It is also conceivable that through the at least one tubular through opening a required cabling, in particular hydraulic lines, is/are passed for operation of the harvesting attachment. Particularly, the through opening completely extends from one side wall to the opposite side wall of the frame. It can be advantageous when the tubular through openings are configured as a continuous tube. The moment of resistance to bending can be increased thereby.
It is also conceivable that the struts form a honeycomb structure or strut system inside the cavity of the frame. Due to the honeycomb structure, which consists of two-dimensionally arranged, in particular hexagonal cavities, a particularly stable construction of the frame is obtained and at the same time a substantial saving of material is achieved.
Another advantageous embodiment is characterized in that the frame consists of segments which are connectable or connected with each other. It is conceivable that in its width the frame is divided into segments of the same size or into segments of variable size. The connection of the individual segments in particular is effected by screwing the side walls to each other, whereby a positive and/or frictional connection of the segments is obtained. An advantage of the division of the frame into individual segments exists in that the geometry, in particular the width of the frame can also be varied after the production of the frame by adding or removing a segment. This opens up the opportunity for the user of the harvesting attachment to possibly adapt the harvesting attachment to the existing working conditions. Furthermore, the production of such harvesting attachment also can be rendered less expensive due to the division into individual segments. In particular, one segment of the frame as such has at least part of the above-mentioned features of the present disclosure. Accordingly, an individual segment may have an L-shaped angular shape which includes at least one cross strut and/or at least one longitudinal strut. Particularly, an individual segment includes six cross struts and three longitudinal struts as well as two side walls which extend in a direction parallel to the longitudinal struts, wherein the cross struts are arranged vertical to the side walls. The six cross struts can also be interpreted as two broad cross struts arranged on different planes, wherein the cross struts include recesses. The segments can include tubular through openings. Advantageously, the tubular through openings of adjacent segments are in alignment with each other and are connected with each other. The moment of resistance to bending can be increased thereby.
The frame or the segments may be made of cast light metal. For manufacturing the cavity inside the casting, commonly used methods known from the prior art are employed. The resulting recesses in the outer wall of the frame or the segment are covered by at least one sheet mounted on the outer wall comprising the recesses. In particular, the recesses are arranged on the front side of the L-shaped segment or frame and are concealed or closed by two sheets covering the entire front wall of the L-shaped frame or segment, so that during operation of the harvesting attachment no crops or small parts can fall into the cavity of the frame.
It is also conceivable that the frame or a segment is manufactured by means of a light-metal welding method.
Particularly, the frames or the segments are made of aluminum.
Alternatively, the frame or the segments are made of plastics, where they are manufactured by a plastics injection molding method, for example.
The outer wall may have a wall thickness in the range from 4 mm to 6 mm, particularly 4 mm. It is conceivable that a frame or a segment with a wall thickness of 4 mm is made by means of a gravity die-casting method.
The harvesting attachment of the present disclosure advantageously comprises a cutting unit and is mounted on a combine-harvester. In addition to the cutting unit all further components required can be mounted on the harvesting attachment of the present disclosure.
Furthermore advantageously, the harvesting attachment comprises a corn adapter for a corn chopper.
An embodiment of the present disclosure will be explained in detail with reference to the attached drawings, in which: